Thick As Thieves

Posted by ESC on January 08, 2002 at

In Reply to: Thick As Thieves posted by Tony Zavaleta on January 08, 2002

: Any thoughts on this expression's origin?

From a previous discussion:
The OED says "close in confidence; intimate; familiar" There's a reference to 1833, but that quote calls it a proverb, so it's older.

The Dictionary of Cliches by James Rogers (Ballantine Books, New York, 1985) says "thick as thieves" means "intimate, conspiratorially close." And it also refers to an 1833 quote -- from "The Parson's Daughter" by Theodore E. Hook. "She and my wife are thick as thieves, as the proverb goes."